Cameras with more dynamic range allow you to take photos with dramatic differences in highlight and shadow areas while retaining detail in both.
Think of a brilliant sunset on a rocky beach: Bright sunset in the background, with dark rocks in the foreground. High dynamic range means more of the extremes will be faithfully reproduced.
Dynamic range test data courtesy of DxO Mark.D90 test data on DxO Mark D3100 test data on DxO Mark
Cameras with longer battery life can take more photos before exhausting their batteries.
Special note: The measurement standard for battery life stipulates that if a camera has an internal flash, it must be used for 50% of photos taken. For this reason, comparisons of one camera with an internal flash to another without will not be comparable